Preparation Of Resveratrol Nanocomposite Gel:in Vivo And In Vitro Evaluation

Resveratrol(Res)is a hydroxystilbene polyphenol compound,which is widely distributed in nature.Resveratrol has many pharmacological activities such as anti-tumor,anti-bacterial,cardiovascular protection,anti-platelet coagulation,prevention of atherosclerosis,reduction of endoplasmic reticulum stress level in diabetic kidney tissue,and maintenance of homeostasis of intracellular environment.In addition,there are many reports about resveratrol’s anti-oxidation,anti-free radicals and inhibition of melanin production,but there are few studies on resveratrol’s use in the treatment of skin pigmentation.Resveratrol is insoluble in water and has poor stability,which limits its application to a large extent.Based on the effect of resveratrol on the inhibition of melanin production and resveratrol,the resveratrol microemulsion gel was prepared by microemulsion solubilization technology,and the best formulation and preparation process were screened.The safety and efficacy of the resveratrol microemulsion gel were evaluated,providing experimental basis for the development and application of resveratrol as skin care product.Part One Pre-prescription studyObjective:To establish a method for determining the content of resveratrol,determine the oil-water partition coefficient of resveratrol,determine whether it is suitable for transdermal drug delivery,and screen suitable transdermal receiving media.Methods:The content of resveratrol was determined by high performance liquid chromatography.The specificity,accuracy,precision,stability and recovery of the chromatographic conditions were investigated.The oil-water partition coefficient of resveratrol was calculated by determining the solubility of resveratrol in n-octanol/water system.To investigate the solubility of resveratrol in different receiving media and select suitable transdermal receiving media.Results:The established conditions of high performance liquid chromatography were characterized by high specificity,stability,precision and recovery.The oil-water partition coefficient of resveratrol was 2.19~2.22,which was suitable for transdermal drug delivery.The transdermal receiving medium of PEG-400 saline was determined to be 30%.Conclusion:The Established chromatographic conditions meet the methodological requirements and can be used to determine the content of resveratrol.The oil-water partition coefficient of resveratrol is suitable and can be used as a transdermal drug delivery agent.30%PEG-400 saline meets the leaky groove condition and can be used as a transdermal receiving medium in vitro.Part two Preparation and quality evaluation of resveratrol microemulsion and microemulsion gelObjective:The formulation and preparation technology of resveratrol microemulsion and microemulsion gel were investigated and evaluated.Methods:The best formulation of microemulsion was screened by pseudo-ternary phase diagram method,taking particle size,PDI,stability and maximum drug loading as evaluation indexes.Taking the viscosity and appearance as evaluation indexes,the formulation and technology of microemulsion gel were screened out by single factor study,and its physicochemical properties were investigated.Female SD rats’abdominal skin was used to investigate the transdermal effect in vitro and skin retention in vivo.Results:The final prescription of resveratrol microemulsion was Res 2.5g,glycerol triacetate 6.0 g,RH-40 24.7 g,PEG-400 12.3 g and distilled water57.0 g.The final formulation of the microemulsion gel is:Resveratrol microemulsion 80.0 g,glycerin 5.0 g,Carbomer 940 0.8 g,distilled water15.0 g,adjust pH to 6~7 with proper triethanolamine.The particle size of the microemulsion was 15.30 nm,PDI 0.344 and viscosity 12417~12557 cP,pH6.17±0.04.The steady skin penetration rates of suspension,microemulsion and microemulsion gel were 5.01,23.46 and 33.80 g/cm~2/h respectively.The skin retention of microemulsion gel 12 h and 24 h was higher than that of microemulsion group and suspension group.Conclusion:The prepared microemulsion has the advantages of clarity,transparency and viscosity,and increases the percutaneous penetration and skin retention of the microemulsion.Part three Safety and efficacy evaluation of resveratrol microemulsion gelObjective:To investigate the safety and efficacy of resveratrol microemulsion gel as whitening and skin care products.Methods:The safety of the preparation was evaluated by oral toxicity test in mice and skin patch test in human.To investigate the effect of the preparation on the melanogenesis of A375 human malignant melanoma cells and zebrafish body surface,and to evaluate the whitening effect of the preparation.Results:The mice were orally administered with 200 mg/kg body weight supplements,microemulsions and drug solutions for one week.The mice had no significant weight change,normal water intake,food intake and limb activity,and no pathological changes in the tissue sections of the main organs.The results of human skin patch test were negative.The tyrosinase activity and melanin content in A375 cells decreased gradually with the prolongation of treatment time.The effect of resveratrol microemulsion group on inhibiting melanin production on zebrafish body surface was better than that of suspension group.When the concentration of melanin is 1μmol,the inhibition of melanin production is the best.Conclusion:The prepared resveratrol microemulsion gel has the advantages of whitening efficacy,high safety,no irritation to the skin,and has certain development value in the field of skin care products for the treatment of skin pigmentation.